Loudness Range (LRA) quantifies loudness variation within a programme as a supplement to integrated loudness

Loudness Range (LRA), measured in LU and defined in EBU Tech 3342, describes the statistical distribution of loudness variation within a programme — how much loudness fluctuates between quiet and loud passages. It is computed from short-term loudness values (3-second windows). LRA supplements integrated Programme Loudness: a film soundtrack may share the same -23 LUFS target as a radio programme but have a much higher LRA (wide dynamics). EBU R 128 recommends LRA to evaluate a programme’s loudness variation and whether dynamic treatment is needed before distribution. LRA is not recommended for programmes shorter than one minute, which have too few data points.

Examples

A classical orchestral recording: integrated -23 LUFS, LRA 20 LU (wide dynamics, may need gentle limiting for broadcast). A brick-walled pop master: LRA 4 LU (heavily compressed). The LRA tells you how much dynamic wiggle room is present.

Assessment

How does Loudness Range differ from integrated loudness? Why is LRA unreliable for programmes under one minute? Give a scenario where LRA drives a mixing/mastering decision.